/*
 * The ELepHant Reasoner
 *
 * Copyright (C) Baris Sertkaya (sertkaya.baris@gmail.com)
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

#include <stdio.h>
#include <stdint.h>
#include <inttypes.h>

/**
 * Round up to the next highest power of 2.
 * From http://www-graphics.stanford.edu/~seander/bithacks.html
 */
inline uint32_t roundup_pow2(uint32_t value) {
  --value;
  value |= value >> 1;
  value |= value >> 2;
  value |= value >> 4;
  value |= value >> 8;
  value |= value >> 16;
  ++value;

  return value;
}

inline uint64_t hash_string(unsigned char* key) {
	uint64_t hash_value = 5381;
	int c;

	while ((c = *key++))
		// hash_value = ((hash_value << 5) + hash_value) + c; /* hash * 33 + c */
		hash_value = ((hash_value << 5) - hash_value) + c; /* hash * 31 + c */

	return hash_value;
}
